Synthesis of poly (E-caprolactone) and methylacrylate grafted starch for biodegradable plastics

Abstract

Two different biodegradable polymers, poly (𝜖-caprolactone) (PCL) and methylacrylate grafted starch (Starch-g-PMA), were synthesized. The polymerization of 𝜖-caprolactone was carried cut at 85°c, in the solution system, under nitrogen atmosphere, using triethylaluminum as the initiator. The concentration ratio of monomer and initiator was varied. The percentage yield of PCL was obtained as high as 98.76. The graft copolymerization of methylacrylate onto cassava starch was initiated by Ce(IV) ion. Several factors were examined in order to optimise the grafting yield and grafting efficiency. It was found that the highest grafting yield and grafting efficiency was achieved when the reaction mixture was composed of 3.5000 g of cassava starch, 0.7939 M methylacrylate, nitric acid 0.5 X 103 mole and 0.3500 g of triethylaluminum in 140 ml with 15 min addition time of the initiator at 45°c. The synthesized polymers, PCL, Starch-g-PMA, and their polymer blends with poly (vinyl chloride), and poly (vinyl acetate) were casted into films. The films were exposed to five fungi, Penicillium funiculosum, Aspergillus flavus, Aspergillus nlger, Gliocladium Virens, and Chaetomium globosum for 50 days. The results on biodegradability were quite promising. PCL and Starch-g-PMA were more easily biodegradable and the polymer blends of Starch-g-PMA seem to be degraded better than that of PCL.